HP 3580A Service Manual

Section V
ADJUSTMENT PROCEDURES
Model 3580A
d. Adjust A8Cl (LINE GENERATOR ADJ.) for a
single round dot in the top center of the screen.
5-70. 1.F. Filter Alignment.
5- 71. This adjustment aligns the l.F. crystal filters for
proper center frequency and symmetry. The TRACKING
OSC is also precisely adjusted to 100 kHz. This adjustment
should be done if the Bandwidth Tests (Paragraph 5-28) of
the Performance Tests cannot be passed by the instrument.
This adjustment will interact with the Amplitude Calibra-
tion (Paragraph 5-74). If it is performed, the Amplitude
Tests (Paragraph 5-18) of the Performance Tests should be
redone to verify whether any amplitude calibration is
necessary.
Recommended Test Equipment:
Timer/Counter (-hp- Model 5326A)
5-72. Tracking Oscillator and Center Frequency
Adjustments.
a. Position the following front panel controls: (Only
those controls printed in BOLD require a change from the
previous adjustments).
ADAPTIVE SWEEP ................. OFF
DISPLAY ........ All pushbuttons released
AMPLITUDE MODE ............. LINEAR
AMPLITUDE REF LEVEL ....... NORMAL
dBv/LIN - dBm 600 n ............ dBv/LIN
INPUT SENSITIVITY . . . . . . . . . . . . + 20 dB
VERNIER (Amplitude) ............ CAL
(Fully CW)
FREQUENCY ................. 10.0 kHz
START-CTR .................. .START
DISPLAY SMOOTHING ............. MIN
RESOLUTION BANDWIDTH . . . . . . . . 1 Hz
FREQ. SPAN/DIV ............... 0.5 KHz
SWEEP TIME/DIV .............. 0.5 SEC.
SWEEP MODE ................• MANUAL
Option 002: Set dBm 900 .Q/LIN -dBm 600 n
switch to dBm 900 .Q; set INPUT MODE
switch to UNBAL.
b. Set the counter to the Frequency Mode and adjust
the time base/multiplier for a measurement of 100 kHz
with six digits of resolution (100.000 kHz). Adjust for
maximum input sensitivity and either a zero trigger level or
Preset. Select ac coupling on input. If using the -hp- Model
5326A Counter, the controls should be set to:
Sample Rate:
Function:
Multiplier:
Channel A:
BNCinput:
5-20
Fast
Frequency
107
Slope+
AC
Atten: Xl
Level: Preset
Sep.
c. Connect the counter Channel A input to A2TP3.
Adjust the 3580A rear panel TRACKING OSC LEVEL
fully CW. Connect the rear panel TRACKING OSC OUT to
the front panel INPUT.
d. Adjust A2C4 (TRACKING OSCILLATOR 100 kHz
FREQUENCY ADJ.) for a counter reading of 99.999 kHz
to 100.001 kHz.
e. Center the CRT Trace with MANUAL VERNIER.
f. Remove the blue lead between ASTPl and ASTP2
and connect a clip lead between ASTPl and A5TP6.
Momentarily press:
DISPLAY ............... CLEAR WRITE
g. Adjust A5C13 (STAGE 5 100 kHz ADJ.) for a
maximum display indication. Remove the clip lead on
A5TP6 and connect to ASTPS. Adjust ASClO (STAGE 4
100 kHz ADJ.) for a maximum display indication. Repeat
this procedure for A5TP4 (adjust A5C7), A5TP3 (adjust
A5C4), and A5TP2 (adjust ASCl).
h. Remove the cable between the TRACKING OSC
OUT and the 3580A INPUT.
5-73. Symmetry Adjustments.
a. Position the following front panel controls: (Only
those controls printed in BOLD require a change from the
previous adjustments).
ADAPTIVE SWEEP ................. OFF
DISPLAY . . . . . . . . All pushbuttons released
AMPLITUDE MODE ....... LOG 10 dB/DIV
AMPLITUDE REF LEVEL ....... NORMAL
dBv/LIN - dBm 600 Q ............ dBv/LIN
INPUT SENSITIVITY ............... CAL
VERNIER (Amplitude) ............ CAL
{Fully CW)
FREQUENCY ................. 10.0 kHz
START- CTR ..................... CTR
RESOLUTION BANDWIDTH . . . . . . . 30 Hz
DISPLAY SMOOTHING ............. MIN
FREQ. SPAN/DIV ............... 0.5 KHz
SWEEP TIME/DIV ........•.•... 0.1 SEC
SWEEP MODE ................. MANUAL
OPTION 002: Set dBm 900 Q/LIN - dBm
600 n switch to dBm 900 Q; set INPUT
MODE switch to UNBAL.
b. Reposition the internal circuit board shield over
circuit boards A2-A4 {leave AS partially uncovered).
Reconnect. ASTPl to ASTP6 and adjust MANuAL VER-
NIER while pressing and releasing DISPLAY - CLEAR
WRITE to obtain a spike display indication in the center of
the CRT screen.

HP 3580A Specifications

General

Brand	HP
Model	3580A
Category	Measuring Instruments
Language	English